Beat frequency oscillator

A beat buzzer, an electronic circuit of the high -frequency technology with which a sine wave with a low frequency (typically in the audible frequency range ) is produced from the mixture of two closely spaced sinusoidal oscillations of high frequencies. It always consists of two high-frequency oscillators:

• A fconst with a fixed frequency and
• A fvar < fconst with a variable frequency.

The vibrations of both oscillators are mixed, it is caused by the phenomenon of the mixture of the vibration with the frequency f = fconst - fvar. By varying fvar f can be continuously varied over a wide range with a largely constant amplitude.

The field of application for beating buzzer were early electronic musical instruments such as the Theremin or the Ondes Martenot.

In the wireless technology, the same procedure is used when you make in a superheterodyne receiver, a CW signal audible or would like to demodulate an SSB signal. Here, the Zusatzoscillator has the task to replace the suppressed carrier ( in the vicinity of the intermediate frequency). The additional oscillator is briefly called BFO, english beat frequency oscillator.

• Radio receiver technology
• Electroacoustics
• Electrical oscillator
• Electrical circuit